【摘 要】
：
Eurypterids,or sea scorpions,are an important group of mid-Paleozoic chelicerate arthropods whose evolution and palaeoeco-logical significance have attracted much attention in recent years[1-3].One of the most remarkable eurypterid families is Mixopterida
【机 构】
：
State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontolog
论文部分内容阅读
Eurypterids,or sea scorpions,are an important group of mid-Paleozoic chelicerate arthropods whose evolution and palaeoeco-logical significance have attracted much attention in recent years[1-3].One of the most remarkable eurypterid families is Mixopteridae,whose members are quite large and superficially scorpion-like eurypterids bearing highly specialized anterior appendages.Their second,and especially the third,pair of proso-mal limbs are enlarged and very spiny.These limbs were presum-ably used for prey-capture,and analogies can be drawn with the“catching basket” [4] formed by the spiny pedipalps of whip spi-ders (Amblypygi) among the arachnids.Our knowledge of these bizarre animals is limited to only four species in two genera described 80 years ago:Mixopterus kiaeri from Norway [5],M.mul-tispinosus from New York [6],M.simonsoni from Estonia [7],and Lanarkopterus dolichoschelus from Scotland [8];all are Silurian in age and come exclusively from the palaeocontinent of Laurussia,which constrains our knowledge of the morphological diversity,geographical distribution and evolutionary history of the group.Here,we describe a new mixopterid,Terropterus xiushanensis gen.et sp.nov.,from the Lower Silurian (Llandovery) Xiushan Forma-tion of Xiushan (Fig.S1 online),characterized by a unique arrange-ment of spines on prosomal limb Ⅲ;and two incomplete,but larger fossils (Terropterus sp.) from the Lower Silurian (Llandovery)Fentou Formation of Wuhan in Hubei Province (Fig.S1 online).
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